In the world of helicopters, a "boom-strike" is the term for a scenario where one of the main rotors flexes downwards SO much, that the rotor encounters the tail section of the helicopter's fuselage. This only happens under extreme conditions, such as when the rotor blade speed becomes dangerously slow during an autorotation, which results in an a very hard landing... or "splat" as we call 'em. When I saw the picture of Alloy's "Tiara" below, the first thing I thought of was... this gives new meaning to term "boom-strike"! In the case of this picture (or approach) it's not the helicopter's boom you need to be concerned with... it's the boom off the main mast! Obviously the boom is swung out of the way for an approaching heli, but the angle of this picture makes it look like this is a VERY good pilot.